I. ˈ ̷ ̷ˌ ̷ ̷ noun
Etymology: up (II) + side
1. : the upper side or part
2. : an upward trend (as of prices)
this issue has emerged on the upside — Stock Trend Service
appreciable upside progress — Wall Street Journal
II. noun
: a positive aspect
III. ¦ ̷ ̷ ¦ ̷ ̷ preposition
Etymology: perhaps from up + -side (I) (as in alongside )
chiefly dialect : on or against the side of
he turned … and I slapped him right upside the head — Marques Johnson